Conventional electronic devices, and particularly hand-held electronic devices, have user interfaces in the form of a keyboard or a touch-sensitive screen having a keypad area. The keyboards and touch-sensitive screens typically include many keys, with each associated indicia, such as alpha-numeric characters, visible to an operator during use of the electronic device. Keypads for electronic devices have been developed wherein each key is associated with multiple key-stroke functions. As a result, fewer keys are required for the keyboard, thereby allowing for efficient use of space for the keypad.
Typically a key in a keypad has indicia either printed on it or positioned relative to the key so as to be visible to a user. Because each key is usable for multiple input functions, each key is typically activated more frequently than if the key had a single input function. With increased use of the keys, the printed indicia on the keys can be worn off or obscured over time, such as from a user's finger pressing on the keys. The keys also have a tendency to get dirty from use over time. The touch-sensitive screens also experience excessive wear in the keypad area, and the screen can get dirty and visually obscured with use over time.
One way to avoid the drawbacks of dirty keys or touch-sensitive screens on an electronic device is for the operator to use gloves. A gloved finger can also reduce the amount of wear on the key's indicia. A disadvantage experienced when the operator uses gloves is that the glove reduces the operator's touch sensitivity during use of the keypad. Accordingly, the glove can make it difficult for an operator to know when a key has been sufficiently pressed to register a key stroke.
Tactile indicators have been used with keys to provide the operator with an indication of a completed key stroke. If the tactile indicator is too stiff, such that an elevated force is required to execute a key stroke, the keys can be difficult to use and the keys can be damaged if an excessive force is applied to the keys. The problems associated with improper tactile feedback, especially with a gloved hand, is exacerbated when using a touch-sensitive screen because such screens typically do not include tactile feedback devices. As a result, a touch-sensitive screen may be susceptible to damage from excessive pressure when the operator presses the key in an effort to register a key stroke.